Human exploration of Mars will require lots of physical stuff in the form of tools and devices; the best strategy is to minimize the amount of stuff a team brings, while maximizing the amount of stuff that can be produced on Mars. The BBMD will manufacture biopolymers like PHA and P3HB for use by a 3D-printer that will create mission-specific items: for CUBES, simple tools and containers, but these will set the stage for the eventual production of habitats and other large scale objects.
Our goals are: 1) the production of biopolymers suitable for additive manufacture by methanotrophs and the possible simultaneous production of nitrous oxide; 2) Use of these biopolymers and their derivatives to additively manufacture a range of tools, bioreactors and other items for mission use; 3) to find routes to efficient recycling of waste, biomass and printed items. We have determined that there is a great deal of variation in productivity of polyhydroxlakanotate (PHA) bioplastic based on the CH4/COs ratio in the feedstock of the methanotrophs and this differed based on whether or not the additive and polymer modifying substrate, valerate, were added. Results pointed to new mutations and enzyme characterizations that would have to be done to optimize yield ultimately.
Evaluation of biofuel production
Power in the form of fuel is an important aspect in ISRU. The BBMD will turn MMFD outputs into fuels that are useful for ascent or that act as a source of power.
Our goals here are to explore the production of two fuels: 1) monopropellant nitrous oxide by methanotrophs; 2) production alternate biofuels such as biodiesels or hydrazine. We also plan to evaluate multiple fuel-production bioprocesses. We have brought these organisms into lab and have initial estimates of their yields and support requirements. However, in discussion with ISRU and fuel production experts from NASA we now have a better understanding of the current costs of physicochemical fuel production and mission fuel needs. Initial models from SDID indicates that propellant generation would require extraordinary quantities of limited material resources such as H2 and N2 and that this propellant is non-recoverable through the same systems designed for agriculture, life support, and other human-oriented systems. We believe that our initial biofuel targets require evaluation. Over the next quarter, the BBMD will evaluate these targets in collaboration with NASA mission experts and the SDID to better determine the appropriate partitioning of limited resources within the BBMD.